Ignition and starting system for automobiles



Sept. 27, 1938. DOMAN 2,131,026

IGNITION AND STARTING SYSTEM FOR AUTOMOBILES Filed Nov. 30, 1931 NYENTORWIT/155s BY l rrmansvs Patented Sept. 27, 1938 UNITED STATES PATENTorncs IGNITION AND STARTING SYSTEM FOR AUTOMOBILES New York ApplicationNovember 30, 1931, Serial No. 578,029

This invention'relates to certain improvements in ignition and startingsystems for internal combustion engines to be used more particularly asthe motive power for automobiles and other motor vehicles in which thespeeds of operation are widely variable.

These machines are usually equipped with a storage battery and anengine-driven electric generator for supplying current to the ignition10 system and other .translating devices, together with an electricmotor for starting the engine and adapted to be operated by current fromthe storage battery through the medium of a suitable electn'c switchunder the control of the operator.

It has also been proposed to control the battery current'to the startingmotor through the medium of a normally closed self-closing supplementalswitch which is connected in the starting motor circuit in series withthe manually operated master switch and is adapted to be automaticallyopened by suction from the intake manifold of the engine or by someother equivalent means as soon as the engine begins to operate under itsown power.

This method, however, so far as l am aware,.

and to hold itopen to pr'event re-engagement of the starting motor withthe engine when the latterv is operating under low speeds or until theengine has actually stopped.

The main object of the present invention is to provide simple andeflicient means controlled by' a single manually-operated electricswitch for automatically and instantly operating the starting. motor tostart the engine in case the latter should stop, by stalling orotherwise, and also to automatically open the motor circuit imme- 40diately upon the starting of the engine, and to keep said circuit openas long as the engine is operating under its own power at any speed.

One of the specific objects is to control the operation of the startingmotor through the medium of an automatic switch operating in conjunctionwith the manually operated master switch in the battery circuit and alsoto utilize the battery current for exciting the field of the generatorfor increasing the voltage output of said generator particularly underits lower speeds as determined bythe speed oi the engine when operatingunder its own power.

Another specific object is to utilize this increased voltage of thegenerator for the operation of an electromagnetic switch for opening thebattery circuit to the starting motor and thereby to prevent theoperation of the latter while the engine and generator are operating atany speed.

Other objects and uses relating toc specific parts of the system will bebrought out in the 5 following description. I

The ignition and starting system is represented diagrammatically in thedrawing and comprises a dynamo electric machine or generator G of thethird brush type and a storage battery B for 10 supplying current to asuitable ignition device I and to a starting motor M through the mediumof a master switch S and other electric elements hereinafter described.

The battery 3' is connected across the main l5 brush circuit of thegenerator G through the medium of a conventional reverse relay switch Rwhich is arranged to automatically close said circuit through thebattery for charging purposes when the voltage output of the dynamoexceeds 20 that of the battery as determined by the speed of the engine.

For this latter purpose, the normally open contacts 1' of the relayswitch R are connected by wires I and '2 respectively, to the positivepole 25 of the battery B and to the positive brush a of the dynamo G,the other side of the relay R and the other dynamo brush 9 beinggrounded at l to complete the dynamo circuit through the relay andbattery. 30

The positive pole of the battery and also the positive brush 9 of thedynamo are connected by wires I, l and I to one of the contacts s of theswitch 8 while the other contact 8' is connected. to the shunt fieldwinding sh of the dynamo G 35 for separately exciting the samefor apurpose presently described;

The ignition system I is similar to that set forth in my Patent No.1,957,393, May 1st,'1934,.and therefore need not be specificallydescribed herein 40 except that it is connected by wires 6 and l to thecontact s' and to the shunt field winding sh respectively and that itincludes a spark coil 0 and a circuit breaker 9 together with anon-inductive electrical resistance II and a condenser ll arrangedsomewhat in the relation shown.

The starting motor M may also be of the conventional type and when themaster switch s is closed, is adapted to be operated by current from wthe battery B through the medium of a normally open supplemental switchA having a pair of relatively fixed contacts I l and II and a movablecontact member I! whichis normally held in its open position by. aspring ",but is adapted to u be closed upon the'contacts by means of anelectromagnet or solenoid M.

One of the contacts as it is ccnnectedto the positive pole of thebattery B by means of a wire l5 and wires 4 and 8 while the othercontact member as l l is connected to one of the-brushes m through themedium of a wire l6 and the series winding w of the motor, the otherbrush as m being grounded to complete the battery circuit through themotor and return for bperating said motor when the supplemental switchmember i2 is closed upon the contacts H and H by the energizing of theelectromagnet H.

For this latter purpose, one end of the winding of the magnet i4 isconnected by a wire H to the contact s of the switch S and thencethrough said switch (when closed) and wires 5, 4 and l to the positivepole or the battery E, the other end of said winding being connected bywires l8 and It to one of the contacts as c of a normally closed switch(1.

The other contact as c of the switch C is mounted upon an armatureconductor 6 which, in turn, is electrically connected to the groundedcore 6' of an electromagnet E having its winding e" connected by wires20 across the main brush circuit of the dynamo G for a purpose presentlydescribed.

A magnetic element F surrounds the contact member I I and is adapted tobe energized by the battery current passing through said contact memberand through the wire IE to the starting motor M when the switch A isclosed by the energizing of the electromagnet H.

The winding of the electromagnet M is connected through the wire I8 andan additional wire 2| to one of the contacts as 7 of a. normally openelectric switch J having its other contact 7" mounted upon a movablearmature member K which may be supported in any suitable manner with oneend in attractive relation to the magnet F so that when the magnet isenergized immediately following the closing of the switch A, thearmature K will be operated to close the switch J against the action ofa retracting spring is, said armature being grounded to complete thebattery circuit through the then closed switch J.

The spring k may be adjusted to open the switch J when the currentrequired for operating the starting motor M is reduced to a suitablevalue or as soon as the engine begins to operate under its own power.

Operation When it is desired to start the engine, the switch S is firstclosed, thus causing a part of the battery current to flow through wiresI, I and 5, and switch S and thence through the shunt field winding shof the generator G and return to the battery for separatelyexciting thefield winding and thereby increasing the voltage output of the generatorfor ignition purposes when the engine is operating at minimum speedsunder its own power.

This closing of the switch S also diverts a. part electromagnet 54 toclose the switch A which causes a part of the battery current to thenflow through wire I 5, closed switch A, wire l6 and series winding w ofthe motor M and return to the battery for operating said motor to startthe engine in the conventional manner.

Immediately upon the closing of the switch A the passage of the batterycurrent through the contact H and magnet F will energize said magnet toattract the armature K and thereby to close the switch J which allowssaid current to flow from the winding of the electromagnet l4 throughwires it and it and thence through the closed switch J and armature Kand return to the battery B for keeping the switch A closed and thestarting motor in action until the engine begins to operate under itsown power.

The fact that the shunt field Sh; of the dynamo G is separately excitedby current from the battery 38 immediately upon the closing of theswitch S, enables the engine-driven dynamo to quickly build up anincreased voltage in the ignition. circuit under the lowest speed of theengine to as' pose the winding e" of the electromagnet E is connectedacross the main brushes of the dynamo G so that the dynamo currentflowing through said winding will energize the magnet and therebyattract the armature e to open the switch 0,

This opening of the switch C will take place almost immediatelyfollowing the beginning of the operation of the engine-driven dynamo Gdue to the extra excitation of the field winding sh by the batterycurrent.

It will be noted however, that even though the switch C is opened in themanner described, the switch members K and I! will remain closedtemporarily or until the power demand of the motor M is reduced by theoperation of the engine under its own power sufiiciently to allow thespring k to open the switch member K This opening of the switch K breaksthe battery circuit through the windingof the electromagnet I4, therebyde-energizing the magnets H and F and allowing the spring [3 to open theswitch A for stopping the motor M.

The opening of the member [2 takes place in- I is still closed, theelectro-magnet E will be instantly de-energized to allow the switch C tobe returned to its normally closed position, resulting in the successivere-energizing of the magnets I4 and F and consequent automatic operationof the motor M for restarting the engine without any further effort onthe part of the operator, and this automatic operation of the startingmotor will take place whenever and only when the engine ceases tooperate under its own power while the switch S remains closed.

It'is equally obvious that as soon as the engine begins to operate underits own power with the switch S closed, the switches C, A, and J will beagain opened to stop the motor M, and will remain open as long as theoperation of the engine under it own power continues or until the masterswitch S is opened by the operator.

What I claim is:

1. In an electric ignition and starting system for internal combustionengines, an electric battery, an ignition circuit deriving currentfromthe battery and including therein a master switch adapted to beclosed and to remain closed at will, a second battery circuit includingtherein a starting motor and a self-opening starter switch, a thirdbattery circuit receiving current from the ignition circuit at a pointbeyond the master switch and including therein an electro-magnetadapted, when energized, to close the starter switch for startingthe'motor and engine, said third circuit including therein aself-closing switch and having a branch circuit including therein aself-opening switch, an engine-driven electric generator having anexcitation field connected to the ignition circuit at a point beyond themaster switch whereby the field will be excited simultaneously with theenergizing of said magnet, a second electro-magnet responsive to thecurrent energy in the starter circuit for closing the switch in thebranch circuit, means responsive to the generator current for openingthe self-closing switch immediately following the closing of the switchin the branch circuit, and means for opening the second switch when theenergy in the second magnet falls below a predetermined value due to thedecreasing loadupon the starter motor, thereby allowing the starterswitch to open. 1

2. The combination with an internal combustion engine, of an automaticstarting system therefor, comprising a starting motor, a normally brokenstarting motor circuit, an electro-magnetic switch for closing thestarting motor circuit, said switch having an actuating coil, a normallyclosed control circuit for energizing said coil, an electric generatordriven by said engine, a battery connected for separately exciting saidgenerator, means responsive'to the terminal voltage of said generatorfor connecting said generator for selfexcitation over a range ofvoltages above a predetermined value, means responsive to the generatedvoltage for opening said control circuit when the generator=rotates, anda second control circuit for said coil including a relay switch actuatedin accordance with current flowing in the starting motor circuit formaintaining the starting motor circuit energized until the startingmotor is relieved of its load of cranking theengine.

3. The combination with an internal combustion engine, of an automaticstarting system therefor, comprising a starting motor, a normally brokenstarting motor circuit, an electro-magnetic switch for closing thestarting motor circuit, said switch having an actuating coil, anignition circuit forsaid engine, said ignition circuit having a manuallyoperable switch, a control circuit for said coil adapted to be energizedupon the closing of said ignition switch, an electric generator drivenby said engine, a battery connected for separately exciting saidgenerator, means responsive to the terminal voltage of said generatorfor connecting said generator for self-excitation over a range ofvoltages above a predetermined value, means responsive to the generatedvoltage for opening said control circuit when the generator rotates, anda second control circuit for said coil including a relay switch actuatedin accordance with current flowing in the starting motor circuit formaintaining the starting motor .circuit energized until the startingmotor is relieved of its load cranking the engine.

4. In an automatic starting system for internal combustion engines, astarting circuit including a magnetic starting switch, a control circuitfor said starting switch including two sets of contacts in parallel,'oneset being normally closed 'and the other set normally open, anelectro-magnet in the starting circuit energized by the cranking currentto close the second set of contacts,

means actuated by rotation of the engine for 1 opening the first set ofcontacts, and means forovercoming the force of said electro-magnet andopening the second set of contacts when the engine starts.

5. In an electrical system for internal combustion engines, anengine-driven generator, a starting system including a starting motorand a magnetic switch therefor, a control circuit for said magneticswitch including two circuit-closing devices in parallel, one of whichis normally closed and the other normally open, means energized byclosure of said magnetic switch for closing the second said device,means energized by said generator for opening the first said device, andmeans for overcoming said closing means and opening said second devicewhen the engine becomes selfstarting motor for closing its contacts.when the motor cranks the engine, and a spring for openingsaid secondrelay when its coil is weakened by the relief of the load on thestarting motor when the engine starts.

ALBERT E. DOMAN.

